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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
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    <title>Document</title>
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<body>
    <script>
        var age = parseInt(prompt("你现在多少岁了？"));
        console.log("据我估计，五年后，你可能" + (age + 5) + "岁了");

    </script>
</body>

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